Oil acid varnish and product coated therewith



Patented Feb.

This invention on. new vaamsn AND momma coa'rnn 'rnsaswrrn Alfonso M.Alvarado, Wilmington, Del, assignor I. du Pont de Nemours & Company,Wilmington, DeL, a corporation of Delaware No Drawing. Application March7, 1931, Serial No. 520,998

11 Claims. relates to the production of coating compositions andproducts coated therewith, and more pa rticularly it relates toartificial leather finished with an improved top coat. Still morespecifically positions suitable the invention relates to comforfinishing rubber coated fabrics such as are used for automobile tops,

rubber upholstery, etc., products resulting from and to the improvedfinishing. such fabrics with the coating compositions described herein.

This invention has as of coating compositions finishes or top coats forture of artificial leather.

an object the production particularly suitable as fabrics in themanufac- A further object is the production of fabrics, particularlyrubber coated fabrics, provided with a gloss, a deep black color,

excellent durabilit top coat having a high freedom from blueness, y, and

even after prolonged exposure to the Weather.

These objects, in their broader aspects, are accomplished by themanufacture of varnishes from asphalt and fatty acids and application ofthese varnishes, with subsequent baking or dry-- ing,to the article tobe varnishes, which for the finishing of rubber finished. Theseasphaltic are particularly advantageous coated fabrics in themanufacture of automobile top material and artificial leather ingeneral, are conveniently made by blending a solution of asphalt with afree fatty acid derived from drying, semi-drying, or non-drying oils,with or without the addition of the usual varnish driers. however, toadd organic compounds of metals,

which compounds also as blending agents between It is preferable,

function not only as driers but the oil acids and the asphalt. Organiccompounds of iron are particularly valuable as blending agents. Ifdesired,

the oil acids may be heat-treated or blown (either in the presence orabsence of organic salts of metals) prior to blending with the asphalt.In general, I prefer to heat-treat in the presence of an organic'saltorganic compound V ing free fatty acids and asphalt, and the method of ametal, especially an iron Suitable varnishes comprisfor theirpreparation, are indicated in the following fourteen examples:

Petroleum residue Solvent naphtha Turpentine subshliiiIIIIIIIIIIIIIIIIChina wood oil acids Total The asphalt is cool to 425 R, an

Example I Parts by weight asphalt 100.00

heated to 500 F., allowed to equal weight of solvent naphtha is added;and the mixture is stirred until the asphalt is complet ely dissolved.To this solution good retention of gloss is added 80 parts by weight ofa 50% or China wood oil acids in turpentine substitute.

Example 11 Parts by weight Petroleum residue asphalt 100.00 Solventnaphtha ..1 100.48 China wood oil acids 20.00 Turpentine 20,00 Cobaltlinoleate (containing 5.80% Co.) 0.17

Total 240.65

The asphalt is heated to 500 F., allowed to cool to 425 F., an equalweight of solvent naphtha is added, and the mixture is stirred until theasphalt is completely dissolved. To this solution is added 40 parts byweight of a 50% solution of China wood oil acids in turpentine and 0.65parts by weight of a cobalt linoleate solution in solvent naphtha, saidsolution containing 1.45% cobalt.

Example III Parts by weight Petroleum residue asphalt 100.00 Solventnaphtha 110.80 Linseed oil acids 160.00 Turpentine 160.00 Lead resinate(10% Pb.) 2.40 Manganese resinate (6.63% Mn.) 1.20

Tot l "534.40 The :phalt is heated to 500 F., allowed to cool to 425 R,an equal weight of solvent naphtha is added, and the mixture is stirreduntil the asphalt is completely dissolved. To this solution is added 320parts by weight of a 50% solution of linseed oil acids in turpentine,9.6 parts by weight of a lead resinate drier solution, and 4.8 parts byweight of a manganese resinate drier solution, said solutions containing2.50%

.lead and 1.66% manganese, respectively.

The gilsonite is heated to 500 F., allowed to cool to 425 R; an equalweight of solvent naphtha is added, and the mixture is stirred until theasphalt is completely dissolved. To this solution is added 80 parts byweight of a 50% solution of castor oil acids in turpentine, 2.4 parts byweight of a lead resinate solution in solvent naphtha, and. 1.2 parts byweight of a manganese resinate drier solution in solventnaphtha, saidsolutions containing 2.50% lead and 1.66% manganese, respectively.

Example V Parts by weight Petroleum residue asphalt 100.00 Solventnaphtha 153. 63 Oleic a 200.00 Turpentine 200.00 Iron resina 1 23.35

Total 681.98

The asphalt is heated to 500 F., allowed to cool to 425 F., an equalweight of solvent naphtha is added, and the mixture is stirred until theasphalt is completely dissolved. To this solution is added 400 parts byweight .of a 50% solution of oleic acid in turpentine and 82 parts byweight of a solution of iron resinate in solvent naphtha, said solutioncontaining 2.44% iron.

Example VI Parts by weight Petroleum residue asphalt 100.00 Solventnaphtha 130.00 China wood oil acids 240. 00 Turpentine- 240. 00 Ironoleate- 30.00

TotaL 740.00

The asphalt is heated to 500 F., allowed to cool to 425 F., an equalweight of solvent naphtha is added, and the mixture is stirred until theasphalt is completely dissolved. To this solution is added 480 parts byweight of a 50% solution of China wood oil acids in turpentine and partsby weight of a solution of iron oleate in solvent naphtha, said solutioncontaining 4% iron.

Example VII Parts by weight Petroleum residue asphalt"; 100. 00 Solventnaphtha"; 110.93 Soya'bean oil acids 40.00 Turpentine 40.00 Iron resina5.47

Tota 296.40

by weight Petroleum residue asphalt 100. 00 Solvent naphtha 129.40Cottonseed oil acids 160.00 Turpentine 160. 00 Iron linoleate 29. 40

Total 578.

The asphalt is heated to 500 F., allowed to cool to 425 F., an equalweight of solvent naphtha is added, and the mixture is stirred until theasphalt is completely dissolved. To this solution is added 320 parts byweight of a 50% solution of cottonseed oil acids in turpentine and 58.8

parts by weight of a solution of iron linoleate in isolvent naphtha,said solution containing 2.73% iron.

Example IX Parts by weight Gilsonite c 100.00 Solvent naphtha 102. 50Coconut oil acids 20.00 Turpentine 20.00 Iron oleate 2.50

Total 245.00

The gilsonite is heated to 500 F., allowed to cool to 425 F., an equalweight of solvent naphtha is added, and the mixture is stirred until thegilsonite is completely dissolved. To this solution is added 40 parts byweight of a 50% solution of coconut oil acids in turpentine and 5 partsby weight of a solution of iron oleate in solvent naphtha, said solutioncontaining 4% iron.

Example X Parts by weight Petroleum residue asphalt 100. 00 Solventnaphtha 100. 00 Bodied China wood oil acids 55. 1'7 Turpentine 60. 00Iron laurate 4. 83

Total 320.00

The asphalt is heated to 500 F., allowed to cool to 425 F., an equalweight of solvent naphtha is added, and the mixture is stirred-until theasphalt is completely dissolved. To this solution is added parts byweight of a 50% turpentine solution of China wood oil acids bodied withiron laurate. (By iron laurate is meant the reaction product of ironsalts with coconut oil acids). The mixture of China wood oil acids withiron laurate is prepared from the following ingredients as indicatedbelow:

Parts by weight China wood oil acids 91.95 Iron laurate (containing11.43% iron) 8. 05

Total--. 100.00

The China wood oil acids are heated to 385 F. and the iron laurate isadded slowly and with constant stirring. The mixture is then heated to425 F. in the course of one hour and kept at this temperature for twohours.

Example XI t Parts by weight Petroleum residue asphalt 100.00 Solventnaphtha 100.00 Turpentine 160.00 1 Bodied linseed oil acids 140.72 Ironresinate 19.28

Total 520.00

The asphalt is heated to 500 F., allowed to cool to 425 F., an equalweight oi. solvent naphtha is Parts by weight Linseed oil acids 87.95Iron resinate (containing 7.3% iron) 12.05

Total 100.00

The linseed oil acids are mean to 450 F. and the iron resinate isaddedslowly and with constant stirring. 4 The oil acids are then heated to525 F. in the course of one hour and kept at this temperature for twohours.

Example XII Parts by weight Petroleum residue asphalt 100.00 Solventnaphtha 121.90 China wood oil acids 40.00 Linseed oil acids 40.00 Ironresinate 10.90

Total 312.80

The following are examples of formulae con taining pigments. Theingredients are compounded in accordance with the method set forth inthe previous examples.

Example XIII Parts i by weight Petroleum residue asphalt 100.00 Chinawoodoil acids 160.00 Carbon black 26.00 Solvent naphtha.. 364.00 Ironresinate 21.84 Total- ;-:1571.34.

Example XIV Parts by weight Petroleum residue asphalt 100.00 China woodoil acids 320.00 Carbon black 69.32 Solvent naphtha -L 537.23 Ironresinate 43.67

Total 1070.22

Certain oil acids, such as China wood oil acids, are remarkable in theircompatibility characteristics with asphaltic materials, especially withpetroleum residue asphalts. which are generally which are satisfactorilycompatible.

In spite of this exceptional compatibility, I usually do not prefer touse asphalt varnishes above 20 gallons in oil acid length when nopigments are used. When pigments are used, however, forty gallonvarnishes can be employed with excellent results. To a certain extent,of course, the preferred gallon lengths depend upon the kind of oilacids used Thus, castor oil acid varnishes of longer gallon length than5gallons cannot be satisfactorily prepared, whereas with China wood oilacids gallon varnishes can be prepared A gallon oil length, as usedinthe varnish trade, designates a gallon of oil per 100 pounds of gum.By weight, this is generally about 8 pounds of oil to 100 pounds of gum.The terms gallon or gallon length or gallon oil acid length, as usedherein, designates 8 pounds of oil acids per 100 pounds of 'asphalt ormixture of asphalt with resin, such as ester gum, limed rosin,

glycerol-phthalate resin containingrosin in com-- bined form, and oilsoluble phenol-formaldehyde resin. For example, a 5 gallon asphalt-oilacid varnish contains approximately 40 pounds of oil acids to 100 poundsof asphalt.

Instead of blending solutions of asphalt and free fatty acids, as in theexamples, the asphalts may be blended with the oil acids at elevatedtemperatures, the blend diluted with the required amount of solvent, andthe drier or iron organic compound added to the mixture. 7

It is desirable, in some instances, to use combinations of asphalts withmixtures of oil acids. When mixtures of oil acids are used, it issometimes desirable to heat-treat or toblow one of the oil acids or themixture of oil acids prior to blending with the asphalts. Substantialimprovements may sometimes be obtained by using mixture of oils with oilacids in the preparation of these varnishes. In order to increase thedurability and to improve the drying qualities of these varnishes,pigments maybe incorporated therewith. When pigments are used, however,it is preferred to use pigments which will not react with the oil acids.In varnishes designed for use under severe conditions of weathering, Iprefer to use a steam refined asphalt in preferonce to asphalts refinedby other methods, such as by blowing with air. The term steam refinedpetroleum residue asphalt varnish, as used herein, is intended todesignate coating compositions in which the principal film-formingconstituents are steam refined petroleum residue asphalts and drying oilacids. However, in some cases it is advantageous to use air blownasphalts,

gilsom'te, or other bitumens in place of steam refined petroleum residueasphalts. When other asphalts or bitumens are used; however, a lowerorder of durability is generally obtained than when steam refinedpetroleum residue asphalts are used. Whereas I have mentioned ordinaryvarnish driers and iron organic compounds as desirable ingredients ofthese varnishes, it will be apparent that inorganic salts of cobalt,lead, manganese, iron, or other metals, not ordinarily used as varnishdriers, may be added and caused to react with the oil acid components ofthe varnish, thus forming compounds efiective as driers or blendingagents.

The process of the present invention finds wide application in themanufacture of rubber coated fabric for automobile top material. In the.onecoat system, which is the simplest form of my invention, the coat ofasphalt-oil acid varnishjected to heating at'a suitable temperature andfor a suflicient time to vulcanize the rubber and to thoroughly fuse thevarnish film. By this of cure depend on the rubber compound, and'especially on the kind and quantity of vulcaniz-' ing agent used. As arule, the temperature will lie between 240 F. and 275 F., and the timeof cure'will be from 30 minutes to 3 hours.

When using my two-coatsystem, I first apply to the uncured rubber anintermediate coat. of varnish which is preferably more flexible than theasphalt-oil acid varnish used as the final coat. Excellent results areobtained, however, through application of two coats of the asphaltoilacid varnish. The intermediate coat may be air-dried, if desired, thatis, dried at room temperature, but it is more advantageous from the coststandpoint to use a force-dry, that is, dry at an elevated temperaturebut below the vulcanizing temperature of the rubber. Thus, I usually drythe first coat varnish by heating it up to 250 F. to 270 F. in one hour,after which I apply the final varnish coat and finish by baking at atemperature of about 240 F. to 275 F. for such time as is required tocomplete the vulcanization of the rubber.

The following is an example of a suitable un dercoat varnish for theabove varnishes:

Example XV Parts by v weight Carbon black 2.5 Bodied China wood oil anddrier 20.0

Bodied linseed oil and drier 20.0

In some cases it is advantageous, after applying the intermediatevarnish coat, to bake at the vulcanizing temperature for a portion ofthe vulcanizing period and to complete the vulcanization of the rubberby baking at the same'tempcrature after the final coat of varnish hasbeen applied. This procedure somewhat shortens the total time requiredto. complete the process, but it is important that care should be takenon the one hand to avoid overvulcanization of the rubber, and on theother hand that the final coat should receive not less than about onehours treatment at the full vulcanizing'temperature in order to producethe best results and to properly condition the varnish film. However, Ido not wish to limit my invention to a process which involves-baking thefinal coat of a two-coat system, since the final coat of varnish may beairdried or dried at only slightly elevated temperatures. This method isnot, however, so desirable because the luster retention of the finish issomewhat reduced when the air-dry procedure is followed.

The two-coat system is preferred to the onecoat system, especially overa rubber coated fabric, because it has greater flexibility and retainsits gloss for a longer time. Without limiting myself thereto, I believethis is due to the elastic coat of intermediate varnish acting as abuffer or bridge between the extremely elastic rubber compound and thecomparatively inelastic top coat of varnish.

The varnishes herein disclosed, whether airdried or baked, are usefulfor finishing fabrics in the production of artificial leather generallyand are especially valuable for finishing-rubber coated fabricssuch asare used on automobile tops, rubber upholstery, etc. These asphalt-oilacid varnishes are superior in compatibility and durability to othervarnishes used for this purpose with which I amfamiliar. In addition tobeing more compatible, these varnishes do not wrinkle when baked overrubber coated fabrics even when comparatively large amounts of raw Chinawood oil acids are used. The excellent compatibility of these varnishesmakes for good initial luster, freedom from grit, and absence of bluevalleys or haze. An outstanding advantage of these varnishes over, thoseheretofore used is their exceptional long retention of luster on outdoorexposure.

With respect to the application of my improved varnishes to fabrics forthe production of products having the characteristics of artificialleather, my process has-been described in connection with rubber coatedfabrics, since these represent the preferred embodiments of theinvention, but it is apparent that the finishes disclosed herein may beapplied as top coats to flexible sheet material in general, such ascloth and paper fabrics or leather. My improved coating compositionsmayalso be used for the production of artificial leather by finishingcoated materials other than rubber coated materials such asnitrocellulose coated and linseed oil coated fabrics. The terms fiexiblefabric sheeting and fabric sheet material, as used herein refer,therefore, to fabrics such as cloth or paper which may be coated with alayer of material such as rubber or pyroxylin; by spraying, spreading,calendering, or by other known methods of application.

-As many apparently widely different embodiments of this invention maybe made without departing from the spirit and scope thereof, it is to beunderstood that I do not limit myself to the specific embodimentsthereof except as defined in the following claims: r

I claim:

1. A coating composition comprising a mixture of free fatty oil acid andasphalt in the proportion-of from 20 to 320 parts by weight of the freefatty oil acid to parts by weightof asphalt.

3. The coating composition set forth in claim 1 in which the free fattyoil acid is drying oil acid. 4. The coating composition set forth inclaim 1 in which the free fatty oil acid is linseed oil acid.

5. The coating composition set forth in claim 1 in which the free fattyoil acid is China wood oil fatty acid.

6. The coating composition set forth in claim 1 in which the free fattyoil acid is oleic acid.

7. -A process for making artificial leather which comprises applying tofabric sheet material a final coating of a varnish comprising asphaltand freefatty oil acid, and drying said coating, said varnish containingfrom 20 to 320 pounds by weight of the free fatty oil acid to 100 poundsby weight of asphalt.

8. A process for making artificial leather which comprises applyinz torubber sheet material a final coating of a varnish comprising asphaltand free fatty oil acid, and drying said coating, said varnishcontaining from 20 to 320 pounds by weight of the free fatty oil acid to100 pounds by Weight of asphalt.

9. A process for making artificial leather which comprises applying tofabric sheet material a final coating of a varnish comprising asphalt,drier, and free fatty oil acid, and baking the resulting product, saidvarnish containing from 20 to 320 pounds by weight of the free fatty oilacid to 100 pounds by weight of asphalt.

10. As an article of manufacture, a flexible fabric sheeting having afinal coat of dried varnish comprising asphalt and free fatty oil acid,the free fatty oil acid and asphalt being present in said varnish in thepounds by weight of the free' fatty oil acid to 100 pounds by weight ofasphalt.

11. As an article of manufacture, a rubber coated flexible fabricsheeting having a final coat of dried varnish comprising asphalt andfree fatty oil acid, the free fatty oil acid and asphalt being presentin said varnish in the proportion of 20 to 320 pounds by weight of thefree fatty oil acid to 100 pounds by weight of asphalt.

ALFONSO M. ALVARADO.

proportion of 20 to 320-

